Apparatus for rendering and refining fats



March 30, 1937. c. UPTON APPARATUS FOR RENDERING AND REFLNING FATS Filed Aug. 2, 1953 l I J 0 \o o o o o o o o o o o o o \o o o o o o o o o o o o c o o o o o o o o o o o o r llllllll Mar. 3@,, i937 rags PATENT OFFICE APPARATUS FOR RENDERING AND REFINING FATS g 6 Claims.

This invention relates to the rendering of fats and the like, in which fat and oil yieldingmaterials are subjected to heat treatment so as to liberate free grease or oils. Heretofore it has been a common practice to render fats, such as lards, by subjecting fat or oil bearing substances to heat treatment, and the liberated grease or oil was then removed and separately treatedand refined to place it in marketable condition.

An object of this invention is to provide an improved rendering and refining kettle in which the fats are rendered and the oils and greases liberated therefrom are refined, all in one apparatus and in concurrent operations; with which 1,, the rendering and refining operations may be carried on with a minimum of handling of the materials; which will occupy a minimum of floor space; with which the cooking and refining operations may be carried out in a minimum of time and with a minimum of eiTort; with which the cooking conditions may be changed at will; with which the cooking may be carried on at, above, or below atmospheric pressure as may be desired; with which the solids and residue from the rendering chamber may be easily discharged at the conclusion of a rendering operation without admixture with the refining solids, and vice versa; with which the free grease or oil rendered irom the products will be immediately removed 36 from contact with the fibres of the material being rendered; with which the liberated greases and oils will pick up a minimum of protein and mucilaginous materials; with which moisture may be removed from the material being rendered and also from the free grease during the cooking operation; and which will be relatively simple and inexpensive.

Another object of the invention is to provide improved means for rendering andrefining oils and greases in a complete process and in one self contained unit.

Various other objects and advantages will be apparent from the following description of one embodiment of the invention, and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

in the accompanying drawing:

Fig. 1 is a sectional elevation through a rendering unit constructed in accordance with this in- 59 vention;

Fig. 2 is a sectional plan of the same, the section being taken approximately along the line f Z-2 of Fig. 1;

Fig. 3 is a sectional plan, on a larger scale, of a 55 portion of the floor of the upper compartment, to

illustrate one of the screens for the drainage openings; and

I Fig. 4 is a sectional elevation, of the same portion of the floor of the upper compartment, the section being taken approximately along the line 5 4-4 of Fig. 3.

g In the illustrated embodiment of the invention, the improved rendering and refining kettle includes an upright casing III, which may be formed of superposed sections connected together to form a unit, and havlngjntermedlate of its ends a transverse wall or partition I I which subdivides the interior of the casing into a cooking or rendering chamber orcompartment I2 and a refining chamber or compartment I3, the two chambers or compartments being thus superposed with respect to one another and separatedby the wall or partition II which forms the floor of the upper compartment and the top of the lower compartment. 20

The sides and bottom of the casing ID are steam jacketed, in a manner common in this art, both above and below the floor wall or partition II, and this floor or wall II is also, preferably, similarly steam jacketed. The joints between abutting sections of the casing are made airtight, and for this purpose the abutting faces of the sections may have cooperating ribs and grooves; with suitable gasket material disposed in the bottom of each groove to provide an effective seal at the joints. The sections may be coupled in any suitable manner, such as by screws or bolts, as shown. The top portion of the casing may have a charging dome I4 which is suitably closed by a cover I5, the cover, when closed, being sealed against the open end of the dome I4 with interposed gasket material, by draw bolts or rods IS with adjustable nuts Ilia, the bolts being pivoted to suitable lugs on the dome II and swung into and out of'position for engagement with the cover through suitable slots I! in the periphery of the cover.

Avent pipe I8 opens into the upper compartment I2 through the dome I4, and carries a pressure gaugeIS. The pipe I8 has a branch pipe 20 opening into atmosphere and controlled by a valve 2I, so that any pressure in the casing may be released by opening the valve 2|, or the escape of air or other gases may be shut off through the closing of the valve 2|. The pipe I8 also is connected through a valve 22 to a barometric condenser 23, or other device for creating a partial vacuum or suction, so that by closing the valve 2I and opening the valve 22 a.

partial vacuum may be created in the cooking chamber or compartment [2 of the casing.

The fioor wall or partition H is provided with a plurality of drainage passages 24, extending from face to face of the wall II, so as to establish continuous communication between the upper or cooking compartment 12 and the lower or refining compartment l3. Each of these passages 24 is screened at its upper end by a perforated plate 25 which is countersunk fiush into the upper face of the floor wall II and secured against displacement by countersunk screws 23. The perforations 21 of the plate 25 are large enough to allow free grease and oils to pass through without material opposition, but are small enough so that very little, it any, of the solids or fibres of the material being rendered will pass through the plate.

A drain pipe 28 opens upwardly through the bottom of the casing, which is the bottom or fioor of the lower or refining compartment l3, into the refining compartment, and is controlled by valve 23 so that when the valve 29 is opened, free grease or oil in the refining chambermay fiow oil and becollected in any suitable receptacle, not-shown. The casing in is also provided with a pair of door openings 30 and 31, one for each of the compartments i2 and I3 respectively. These door 'openings extend upwardly some distance from the fioor oi the compartment and are entirely separate from, and out of communication with, one another. A door or closure 32 is fitted to the casing so as to close the door opening 30 and make an air tight closure therewith,

' yet this door 32 is operable into open position as will be explained presently. Similarly a door or closure 33 is fitted to the casing so as to close the door opening 3| in vthe wall of the refining compartment i3, and is operable, when desired, into open position so as to establish communication with the interior of the casing through the door opening 3|.

A driving shaft 34 extends into the casing, and for convenience may extend upwardly through the bottom wall thereof. The space between the shaft 34 and the bearing in the lower wall may be sealed by a suitable packing gland 35. This shaft 34 also extends through an opening 36 in the floor wall or partition II and is. rotatably mounted at its upper endvin a bearing 31 which is supported by projections or a spider-like frame provided on the interior of the casing. The shaft 34 mounts an agitator blade 38 within the lower compartment l3, and also an agitator blade 39 in the cooking compartment l2. The blades 33 and 33 are fixed to the shaft so as to rotate therewith and are so disposed as to move in close proximity to, or sweep the fioor of the compartments in which they are placed and move any solid matter in these compartments toward the door opening of that compartment.

The shaft 34 also carries another blade 40 in the upper part of the compartment l2, and this blade 40 may have a plurality of fins or projecting arms4l thereon to assist in the agitation. Arms 42 may also connect the blades 39 and 40 so as to act as stirrers moving through the interior of the mass of fats or substances being cooked or rendered in the upper compartment II. The shaft 34 is rotated in any suitable man- 'ner, such as by any suitable motor or other source oi. power, not shown, and when rotated-will keep the contents of both compartments agitated. When the doors 32 and 33 are opened, the blades or agitators 33 and 33 in the compartments will shift the solids of those compartments to and through the respective door openings of those compartments.

The cooking chamber or compartment l2 and the refining or drainage compartment or chamber l3 are both of substantial depth, and at the beginning of or preceding the operation of rendering a batch of material, a refining agent of any desirable character is introduced into the lower or refining compartment I3 through a suitable pipe connection |3a in the side of'the casing. For example, activated carbon, soda and other chemicals may be placed in the lower compartment, I3, and as the free grease or oil drains into the lower compartment through the passage 24 from the upper cooking or rendering compartment, it will be thoroughly mixed with the activated carbon and other refining agents or chemicals.

At the conclusion oi. the rendering operation, the valve 23 can be opened and the tree oil or grease in the refining compartment can be drawn ofi, filtered through a filter press to remove the activated carbon, and the grease is then in a marketable condition, after which the cracklings or solids in the upper or cooking compartment I! may be discharged through the door opening 30 by the operation of the agitator 39 which sweeps the solids or cracklings toward and through the door opening 30. Thereafter any fine solids which work through the perforations 21 in the drainage plates 23 into the lower compartment, together with the activated carbon and other chemical agents, still remaining in the compartment l3, can be similarly discharged through the door opening 3 I. With this arrangement the cracklings will be kept separate from the activated carbon and other refining substances, and thereby the cracklings will bring a higher price than when mixed with the activated carbon or other'refining materials.

' In operation, the refining agent, such as activated carbon, soda and other chemicals, are

placed in the lower compartment l3 and the door After'the charge has been placed in the cooking chamber l2, the cover I! will be tightly closed again, and heat turned on in the steam jacketed walls of both chambers and the steam jacketed 'fioor or wall II. The valve 28 is closed and, as

the cooking continues, the temperature of the mass in the cooking chamber will be kept uniform throughout the mass by the action of the agitators therein. By suitable manipulation of the valves Hand 22, the internal pressure conditions within the casing may be regulated as desired, and as the cooking continues, free grease or oil will be liberated and will drain promptly through the perforated plates 25 in the refining compartment l3, before this free grease or oil has had a chance, through prolonged contact with the material in the, upper compartment, to pick up protein or other mucilaginous materials. As rapidly as the oil and free grease drains into the lower compartment, it is thoroughly mixed with the heated refining agents, such as activated carbon, soda and'other chemicals, and refined and kept hot or fluid. After all of the free grease orroil has been liberated from the mass in the upper compartment l2, and has been drained into the refining chamber l3, the door 32 in chamber 12 may be opened, and then the continued movetained for the pure cracklings.

ment of the agitator 39 will sweep the residue, which commonly is called the cracklings, through the door opening 30, and after pressing the grease out of the cracklings, this residue or crackling cake may then be sold as a by-product. During this discharge of cracklings, the oil orfree grease in the compartment I3 is thoroughly mixed with the refining agent, and then the valve 29 may be opened to drain off the refined oil or free grease which is now in'a marketable or refined condition. After all of the oil or free grease has been drawn off from the chamber [3, the door 33 is opened, and the solid residue containing the activated carbon is discharged through the door opening 3| and suitably disposed of. v

It will be noted that with this arrangement, there will be no mixing of the cracklings with the activated carbon or other refining agents and, therefore, the maximum market price may be ob- If the activated carbon should be mixed with the cracklings, the cracklings would become dirty and black which would materially affect their sales value, although the quality of the cracklings, otherwise than in appearance, would not be materially injured. It is also possible with this apparatus to perform any portion of the cooking operation under a partial vacuum which makes it possible to cook the mass at a lower temperature and to remove the moisture from the material being rendered in the chamber l2, and also to remove the moisture from the material being rendered in the chamber 12, and also to remove moisture from the free grease that collects in the refining chamber I3. Thus, this apparatus is a self-contained unit for the complete rendering and refinement of fats, such as lard.

It will be understood that various changes in the details, which have been herein described and illustrated in order to explain thenature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the-appended claims.

I claim:

1. A rendering and refining kettle comprising a casing subdivided into superposed compartments of substantial depth, the upper compartment being of a size to hold a substantial charge of fat bearing solids, and the lower compartment being of a size to hold a charge of a solid refining agent and also all of the fats that can be liberated from said fat bearing solids, a separate air tight discharge door for each compartment adjacent the floor of that compartment for discharging the contents of that compartment outside of the casing without passing through the other compartment, means for heating each compartment, the floor of the upper compartment having substantially flush with its upper surface a screened drain opening into the lower compartment of a mesh to retain substantially all solids in the upper compartment and drain free grease released in the upper compartment continuously into the lower compartment, an agitator in each compartment with a portion moving in close proximity to the fioor of that compartment, and means for withdrawing free grease when desired from the lower compartment, whereby fats may be rendered in the upper compartment, the solids all retained in that upper compartment, the free grease therefrom drained continuously into the lower compartment, there immediately mixed with solid refining materials, and at the end of the treatment of said charge of fat.bearing material, the refined fat may be withdrawn and filtered to separate it from some of the refining materials, and the solids of said compartments removed separately and without mixing with one another.

2. A rendering and refining kettle comprising a casing having steam jacketed walls, a steam jacketed, horizontal partition extending across the interior of the casing and subdividing it into a plurality of superposed compartments, said partition having a screened passage extending from face to face thereof, so that liquids may descend from the upper compartment to the lower, and practically all solids in the uppercompartment will be retained therein, a valve controlled pipe opening into the lower compartment at the floor thereof to remove free grease therefrom at intervals, said casing having in a side wall thereof a pair of individual doors, one for each compartment and opening into that compartment at the floor thereof, and an agitator in each compartment and approximately sweeping the floor thereof so as to sweep the contents of that compartment toward the door of that compartment, whereby fats may be rendered in the upper compartment, the free grease therefrom drained continuously into the lower compartment and there treated with refining solids and chemicals, all in one concurrent operation, and the solids in each compartment afterwards discharged from the casing separately from one another.

3. A rendering and-refining \kettleweamprising a casing having steam jacketedwall's;--a steam-- jacketed, horizontalpartition extending across the interior of the casing and subdividing it into a plurality of superposed compartments, said partition having a screened passage extendingfrom face to face thereof, so that liquids may descend from the upper compartment to the lower, and practically all solids in the upper compartment will be retained therein, a valve controlled pipe opening into the lower compartment at the floor thereof to remove free grease therefrom-at intervals, said casing having ina side wall thereof a pair of individual doors, one for each compartment and opening into that compartment at the fioor thereof, an agitator in each compartment and approximately sweeping the floor thereof so as to sweep the contents of that compartment toward the door of that compartment, whereby fats may be rendered in the upper compartment, the free grease therefrom drained continuously into the lower compartment and there treated with refining solids and chemicals, all in one concurrent operation, and the'solids in each compartment afterwards discharged from the casing separately from one another, a valve controlled vent for said casing by which an internal pressure at or above atmospheric pressure may be created within said casing during a cooking oper- I ation, and means also connected to said casing for creating a partial vacuum therein at will.

4. A one-stage, lard rendering and refining kettle, comprising a plurality of heated chambers arranged at different levels, the upper of said.

chambers being of a size to hold a substantial charge of fat bearing materials, and the lower chamber being of a size sufficient to hold all of the free fat liberated from said charge and also a charge of a solid refining agent, a passage opening through the floor of the upper chamber, and leading to the lower chamber, a screen across said passage and forming a continuation of the floor across said passage, said screen having a mesh of such finenessthat it passes liquefied fats and prevents passage of any substantial amount of solids of said materials, each chamber having a separate door at the floor level thereof through which all solids in that chamber may be discharged from that chamber and kept separate from the solids in the other chamber, means for drawing ofi liquid fats from the lower chamber, and an agitator and mixer in each chamber, whereby fats may be rendered in the upper chamber, the liquefied fats drained through said screen 10 into the lower chamber as rapidly as liberated, and there immediately mixed with said refining agent in the lower chamber while further iat is being liberated in the upper chamber and immediately drained into the lower chamber. l5 5. A rendering and refining kettle comprising a steam jacketed casing subdivided by asteam jacketed partition into superposed compartments oisubstantial depth, the upper compartment being of a size to hold a substantial charge of fat 2 bearing solids, and the lower compartment being of a size to hold a charge of a solid refining agent and also all of the fats that can be liberated from said fat bearing solids, a separate air tight discharge door for each compartment adjacent the fioor of that compartment for discharging the contents of that compartment outside oi the casing without passing through the other compart- 'ment, means for heating each compartment under a partial vacuum, the fioor of the upper 30 compartment having substantially fiush with its upper surface a screened drain opening into the lower compartment of a mesh to retain substantially all solids in the upper compartment and drain freegrease released in the upper compartment continuously into the lowercompartment, an agitator in each compartment with a portion moving in close proximity to the floor of thatand at the end of the treatment of said charge of rat bearing material, the refined tat may be withdrawn and filtered to separate it from some of the refining materials, and the solids of said com partments removed separately and without mixing with one another.

6. A rendering and refining kettle comprising a steam jacketed casing subdivided by a steam jacketed partition into superposed compartments or substantial depth, the upper compartment being of a size to hold a substantial charge of fat bearing solids, and the lower compartment being oi a size to hold a charge of a solid refining agent and also all of the fats that can be liberated from said iat bearing solids, a separate air tight discharge door i'or each compartment adjacent the fioor of that compartment for discharging the contents of that compartment outside or the easing without passing through the other compartment, means for heating each compartment under a partial vacuum, the floor of the upper compartment having substantially flush with its upper surface a drain opening into the lower compartment with such restrictions as to retain substantially all solids in the upper compartment and drain free grease released in the upper compartment continuously into the lower compartment, an agitator in each compartment with a portion moving in close proximity to the floor of that compartment, and means for withdrawing free grease when desired from the lower compartment, whereby i'ats may be rendered in the upper compartment, the solids all retained in that upper compartment, the free grease therefrom drained continuously into the lower compartment, there immediately mixed with solid refining materials,

and at the end of the treatment of said charge of fat bearing material, the refined fat may be withdrawn and filtered to separate it from some of the refining materials, and the solids of said compart- 

